1. Field of the Invention
The invention relates to a confocal laser scanning microscope with a spot illumination arrangement which provides an illumination beam for the illumination of a sample by points or point groups, a scanning arrangement which guides the illumination beam by points or point groups over the sample in a manner so as to scan, a spot detector arrangement which images, via the scanning arrangement, the point or point group spot of the sample by means of at least one confocal aperture on at least one detector unit, and a control unit which controls the scanning arrangement and reads out the spot detector arrangement.
The invention further relates to a process for laser scanning microscopy, wherein an image of a sample is generated by scanning and confocal imaging of a point or point group spot and means are provided for the illumination of the scanned point or point group spot.
2. Related Art
Confocal laser scanning microscopes of the type stated initially are known in the state of the art, by way of example let reference be made to DE 197 02 753 A1. Recently microscope accessories, in particular confocally imaging laser scanning microscopes, have been used increasingly for spectroscopic exposure technologies. In this way it is possible to measure the spectroscopic properties of a selected sample area without damage or contact. The confocal optical microscope makes possible in this way the selective detection of optical signals which are generated within a diffraction-limited confocal volume whose size lies in the micrometer range. Laser scanning microscopes with sampling laser beams and/or sample feed units can produce with a high spatial resolution two-dimensional or three-dimensional representations of the sample examined. Due to this property, confocal laser scanning microscopy has achieved success for fluorescing samples in the biomedical field, nearly as the standard.
Beyond said fluorescence measurement, said DE 197 02 753 A1 also provides for carrying out a transmission measurement on the sample. For this, a detector can be activated which, relative to the direction of illumination of the scanned laser radiation, lies below the sample and which picks up the transmitted percentage of the radiation beamed in the form of a point via the scanner. Thereby a so-called “transmitted light scan” is realized. The optical linking of the detector lying below the sample presents certain difficulties, in particular since one customarily also provides an optical viewing device for an observer on the microscope part of the laser scanning microscope. This has as a consequence the fact that a change-over between the illumination for the normal microscope and the separate detector for the transmitted light scan is required.